There remains a need for reliable, low cost, electrical connectors which can be subjected to repeated connections and disconnections at desired random locations without damage to the connector components. For example, in standard multiple pin plugs, each pin is connected to a corresponding receptacle in the plug by an independent connection. Repeated attachments of the pin holding component in the receptacle component, along with movement of the pins within the receptacle component, wears down the conducting surfaces of both the pins and the receptacles. The worn down surfaces loose their metalized coating and begin to oxidize. At the same time, the pins may loosen. As a result, electrical contact resistance increases to a point where the connector is considered to have failed.
Electrical connectors utilizing interlocking tapers to maintain intermeshable contact between the electrically conducting components have been disclosed in U.S. Pat. No. 5,071,363 to Reylek et al. This patent discloses an electrical connector comprising intermeshable members. The members cooperate to insure electrical connection in a compression contact as the members interact with each other. Each of the members is of a rigid material and has an electrically insulative body with a structured surface including a plurality of tapered elements. The tapered sides of each member include electrically conductive material such that when the members are intermeshed, there is an electrical connection, which is retained by frictional forces created by the interlocking tapers between the members. The connection between members is maintained until a sufficient force is applied to disengage the members.
The geometry requisite for this intermeshing and subsequent retention is described in U.S. Pat. No. 4,875,259 to Appeldorn. Although this reference does not mention electrical connectors, it describes intermeshable members that can be used in pairs as mechanical fasteners. Each of the members has a structured surface including a plurality of tapered elements, each element having at least one side inclined relative to a common plane at an angle sufficient to form a taper. Upon being intermeshed with the tapered sides of the two elements in contact, the pair of members become frictionally interlocked when the tangent of the half angle of the tapered sides is no greater than the coefficient of friction of the material of the contacting surfaces. Individual tapered elements can be exceedingly small.
The connectors disclosed in Reylek et al. were designed to carry current over distances of centimeters. This is because their relatively thin conductors and rigidity gave rise to substantial resistance at distances beyond a few centimeters. As a result, these connectors remained limited to short distance lengthwise current transport.
Flexible electric current carrying devices, referred to in the trade as "zebra strips" are known. These zebra strips are solid rectangular elastomers with conductive particle slices interspersed along their length. They are made by laminating alternating layers of conducting and insulating materials, followed by skiving. These zebra strips are limited to conducting electric current along their thickness or width. They exhibit the same drawback as the Reylek et al. connectors, in not being able to conduct current along their length, because the conductive slices are high in resistivity.
Electrically conducting particles have been imbedded in elastomers, such as rubbers. These particle imbedded elastomers are made by orienting the particles in the rubber with magnetic fields during manufacturing. However, these particle imbedded elastomers exhibit high resistivity, and as a result are used only for electric current transport over lengths no more than a few millimeters. More common uses of these particle imbedded elastomers include gaskets and seals for doors on electrical cabinets and the like.
It has also been desirable to eliminate the use of wires, cables or other long cord lengths from electrical devices to an apertured electrical receptacle, i.e., telephone jack, antenna connector, low voltage electrical outlets. Long cord lengths detract from the aesthetics of a room and may cause injuries if people step on or trip over the cord. Furthermore, the cord length and fixed receptacle position may constrain the location of an electrical device to an inconvenient position.